Security high at arms show

But protests at the Defence Systems & Equipment International (DSEi) event at the ExCel Centre in London's Docklands were muted.

Police arrested 51 people in the run up to the event and a further three people were detained this morning after red paint was thrown over a walkway leading to the centre.

Anti-arms activists had pledged to mount demonstrations in an effort to disrupt the show.

A small group of demonstrators shouted "shame on you" at delegates queuing for entry to the event as it opened at 9.30am, but they made no attempt to break through security.

Nearby around 100 protesters with props including a cardboard tank listened to music and chanted peace slogans.

Heavy duty weaponry

Inside, delegates browsed hundreds of stalls loaded with heavy duty weaponry and chatted over coffee with apparently no concern over the protests.

One delegate, who did not wish to be named, said they had come to expect controversy.

"It happens every time, so we're used to it," he said.

Military top brass and defence ministers from a number of countries including Algeria, Angola, Colombia, Pakistan and India were expected to attend the show, which lasts until Friday, to see exhibits from some 950 companies.

Hardware from around the globe

The event showcases a range of military hardware from around the globe.

Several companies were showing details of systems that can be installed on civilian aircraft to confuse surface-to-air missiles.

More than 2,600 security guards and officers have been assigned to the job of policing the site, including 25 Ministry of Defence police officers.

Policing bill

The policing bill was expected to run to more than £1 million but the show's organisers, Spearhead Exhibitions, were not contributing to the cost.

Scotland Yard denied claims by civil rights group Liberty that officers were using their powers under Section 44 of the Terrorism Act at the arms show.

A spokeswoman said police were using their powers to stop and search under Section One of the Police and Criminal Evidence Act.

A spokesman for DSEi insisted the event was not an arms fair.

"This is an exhibition, mainly for contractors and sub-contractors. It's an industry-to-industry show," he said.

Every exhibitor signed a form saying it would not bring illegal weapons systems, and these were monitored by the Ministry of Defence, he said.

About half the exhibitors are British firms, with 20% from the US and the remainder from other Nato countries.